Method of producing colored smoke



Feb. 8, 1938. E NEUKIRCH 2,108,019

METHOD OF PRODUCING COLORED SMOKE Filed 001;. 1'7. 1936 [Eberhard Neuka'rch lnvenfor By His Afforneys AW Ma-$194 Patented. Feb. A 8, 1938 v UNITED STATES METHOD OF PRODUCING COLORED SMOKE Eberhard Neukirch, Bitterield, Germany, "an... to I. G. Farbenindustrie Aktiengesellschait, Frankiort-on-the-Main, Germany Application October 11, 19 36, sci-m No. 106,261 In Germany November 6, 1935 10 Claims.

This invention relates to a method; of and means for the production of colored smoke and more particularly to smoke-producing charges for bombs, projectiles, and the like.

For the purpose of indicating hits during bombingpractice, it has hitherto been customary to charge the bombs with fuming sulphuric acid. Such a fillin however, merely furnishes white smoke which, especially in winter, contrasts only slightly with the landscape. Moreover, fog has been produced by allowing chlorosulphonic acid to act on lime, thereby generating a dense white mist.

It has now been ascertained, in accordance II with the present invention, that a yellow to brown smoke is obtainable by the action of chlorosulphonic acidon chromium compounds containing chromium in the hexavalent i'orm.

The eiiect oi the smoke thus produced can be intensified bythe' use of an additional substance, such as lime. which generates smoke in conjunction with chlorosulphonic acid. The yellow or brown coloration of the smoke is due to the .iormation or chrcmyl chloride, which, although h'aving a boiling point 01' 117' 0., is.

owing to the considerable heat generated by the reaction between the compounds, of the mixture, volatiiized when the smoke is evolved. The chromyl chloride can also be'gcnerated, in known manner, by allowing fuming sulphuric acid to 30 act upon mixtures of calcium dichromate and common salt. The best resultsarepbtained by using equal parts byweight oi ammonium dichromate and chlorosulphonic acid, the fammonium dlchromate being'preierably employed m'ms mm of fine powder, thereby ensuring a.

55 smokecharge in accordance with tion, is illustrated diagrammaticallycomp nring drawing, which represen tudinai section oi such a bomb.

In said drawing, i denotes the cement shell having a cap 2, enclosing a chamber 3 housing a small glass tube 4 containing chlorosulphonic acid, and surrounded with the chromium com--- I pound 5, which maycontain lime in admixture. 5 6 is a tail piece attached .to said shell and'provided with flnsl. The impact of the bomb on the target smashes the glass tube, thereby bringing the chlorosulphonic acid into reaction with the surrounding chromium compound. The 1 relative proportions of the chlorosulphonic acid and of the surrounding chromium compound may be so adjusted that a yello to dark brown cloud of smoke, lasting for 5 to 0 seconds, is produced. is

I claim: a

1. A method of producing colored smoke which comprises causing a chromate compound to react with chlorosulphonie acid.

2. A method of producing colored smoke which comprises causing ammonium dichromate to react with chlorosulphonic acid.

3. A method 01' producing colored smoke which comprises causing potassium chromate to react with chlorosulphonic acid in the presence of caustic lime.

4. A smoke-producing charge for practice bombs, comprising a-breakable' tube containing chlorosulphonic acid, and a chrcmate compound adjacent said tube. I

5. A smoke-producing charge for practice bombs, comprising a breakable tube containing ota-chloride compound.

8. A method oi producing colored smoke which "comprises causing calciumdichromateto react with fuming sulphuric acid in the presence of. common salt.

9. A smoke-producing charge for practice bombs, comprising a breakable tubecontaining iumingsulphuricacidandamixtureotachrm. mate compound and a chloride compound adso .iacent said tube.

. 10. A smoke-producing charge for practice bombs; comprising a breakable tube containing fuming sulphuric acid, and a mixture oi calcium dichromate and common salt adjacent said as tube. 

